Composition comprising at least one dry powder obtained by spray drying to increase the stability of the formulation

ABSTRACT

The present invention relates to inhalation formulations of drugs in the form of dry powder for inhalation administration deliverable as such with an inhaler and provided with high deliverability, respirability and stability. In particular, the invention relates to a pharmaceutical composition for inhalation use in powder form comprising a first powder comprising at least a powder (a1) comprising an active agent or a pharmaceutically acceptable salt thereof, in an amount greater than 1% by weight of the powder, leucine in an amount from 5 to 70% by weight of said powder, a sugar in an amount from 20 to 90% by weight of the powder; 
     and a second powder comprising a mixture of a first lactose which has an X50 from 35 to 75 μm, with a second lactose which has an X50 from 1.5 to 10 μm, the content of the first and second lactose in the mixture are respectively from 85% to 96% and from 4% to 15%. The ratio by weight between the first powder and the second powder is from 1/5 to 1/100, and the composition has a fine particle fraction (FPF) greater than 60% and a delivered fraction (DF) greater than 85%.

The present invention relates to inhalation formulations of drugs in theform of dry powder for inhalation administration deliverable as suchwith an inhaler and provided with high deliverability, respirability andstability.

Inhalation therapy with aerosol preparations is used to administeractive agents to the respiratory tract, in the mucosal, tracheal andbronchial regions. The term aerosol describes a preparation consistingof particles or fine droplets carried by a gas (usually air) to the siteof therapeutic action. When the site of therapeutic action involves thepulmonary alveoli and small bronchi, the drug must be dispersed in theform of droplets or particles with an aerodynamic diameter of less than5.0 μm.

When the target is the pharyngeal region, larger particles are moreappropriate.

Conditions suitable for these treatments are represented bybronchospasm, inflammation, mucosal edema, pulmonary infections and thelike.

Currently, administration of drugs in the deep lung region is obtainedthrough inhalation devices such as:

-   -   nebulizers, in which the drug is dissolved or dispersed in the        form of suspension and carried to the lung as nebulized        droplets;    -   powder inhalers, capable of delivering the drug present in the        inhaler as dry micronized particles; or    -   pressurized inhalers, through which the drug—again in the form        of droplets of solution or suspension—is carried to the deep        lung region by an inert gas expanded rapidly in air by a        pressurized canister.

In all these cases, technological problems have been encountered in thedevelopment of effective products that still limit the administration ofdrugs by inhalation.

From a clinical point of view, an ideal inhalation product should allowdifferent administration methods to be used by the patient, since theinhalers described are generally suitable for different types ofpatients and administration conditions. In general, nebulizer therapy isprevalently used by elderly or pediatric patients, while therapy withdry powder or pressurized inhalers is more suitable for adults. However,the use of nebulizers is currently still considered effective, since thepatient inhales the drug under rest conditions and without using forcedinhalation, which is instead required for an inhalation powder. Instead,in the case of a pressurized inhaler, the product must be takencoordinating inspiration with activation of the device, to prevent thedelivered particles from impacting on the bottom of the throat andfailing to reach the deep lung.

For these reasons, the inhalation formulations used in these three typesof inhalation devices are generally essentially very different from oneanother.

In the case of products for nebulizers, formulations are substantiallyconstituted by solutions or suspensions containing as excipient salts,surfactants and preservatives to ensure isotonicity of the preparation,homogeneity of the particle size distribution in case of suspensions,and protection against microbial contamination.

In the case of pressurized preparations, the composition usuallycontains surfactants, propellants and co-solvents. In inhalationformulations in powder form, the excipients essentially consist oflactose with different particle size, used as diluent.

Some formulation or stability constraints in some cases have limitedindustrial development of inhalation products and, apart fromcorticosteroids, which exist substantially in all inhalation forms, insome bronchodilator and anti-cholinergic active agents some forms ofadministration are not available on the market. These limitations areparticularly important since current respiratory therapy makes use ofcombinations of drugs of different kinds as the most effective techniqueand, in this regard, it has been possible to develop only a small numberof corticosteroid-bronchodilator combinations, prevalently in the formof inhalation powder.

With regard to nebulized forms, the patient is left to extemporaneouslycombine different formulated products, which might even be incompatiblewith one another.

From a therapeutic point of view, it is therefore limiting for a patientnot to be able to take the same drug in different conditions, such as athome, at work, while travelling and in an emergency. In the differentsituations indicated, a patient might be obliged to use differentpreparations containing different active agents.

The most important of the formulation problems encountered in thedevelopment of inhalation products concerns chemical stability inrelation to atmospheric agents, which cause rapid degradation of theinhalation preparation and, consequently, decrease the shelf life of theproduct containing this preparation.

The stability of an inhalation product is particularly important, sinceit must be administered to the deep lung while maintaining its physicalfeatures for quantitative penetration of particles or droplets to thedeepest regions thereof. Added to this is the fact that the number ofexcipients currently approved for inhalation administration andtherefore acceptable in terms of toxicity for the pulmonary tissue isvery limited.

The literature reports examples of dry inhalation powders with highdispersibility in air due to their low density. These powders areusually formulated with a high content of phospholipids, in particulardipalmitoylphosphatidylcholine (DPPC).

A powder of this kind is described in the patent applicationUS2005/0074498 A1, relating to low density particles, with an internallyhollow morphology, obtained by spray-drying with the use of surfactantsconstituted by phospholipids in combination with a blowing agent). Thehollow structure is described as resulting from the precise combinationof the blowing agent and of the surfactant phospholipid. The documentdoes not describe examples of similar morphology obtained withoutphospholipids. The use of phospholipids as surfactants determines theprincipal features of the product obtained and above all its sensitivityand stability in relation to atmospheric agents, which would beparticularly influenced in this case by moisture. Moreover, the patentliterature (US 2001/0036481 A1) indicates values of the phospholipidtransition temperature (Tg) with humidity of 41° C. for DPPC, 55° C. fordi stearoylphosphatidylcholine (DSPC) and 63° C. fordipalmitoylphosphatidylethanolamine (DPPE), the three phospholipids mostcompatible with pulmonary administration.

The transition temperature is defined as the temperature required tocause a change in the physical state of the lipids, from the ordered gelphase in which the hydrocarbon chains are lying flat and closely packed,to the disordered liquid-crystalline phase in which the hydrocarbonchains are randomly oriented and fluid.

These Tg values are all much lower than the characteristic Tg value ofamorphous lactose.

It is known that the closer the Tg is to the temperature of theenvironment in which the preparation is stored, the easier thetransition will be. It is also known that in a system in which the mainexcipient is fluid and loosely packed, the molecular mobility of thecomponents is very high, and consequently has a propensity to causedifferent chemical reactions and degradation of the active agents.

Therefore, the solution of producing porous particles for inhalationadministration with phospholipids does not appear to be supported byreasonable scientific evaluation in relation to the long term stabilityof the product.

The aforesaid patent application, besides application as inhalationpowder, also describes application of these particles in an inhalerdevice with a propellant gas. This administration would be impossiblewith a conventional nebulizer by dispersing the particles in water oraqueous solution, given the incompatibility of the materials with water,above all due to their tendency to float on the surface of the liquid orto dissolve slowly therein.

The concept of “high porosity” or “low density” has been used in asubstantially equivalent manner in the cited patent applications.

In particular, the term “density” has been used not to refer to theabsolute density of the particles, since this, measured with a heliumpycnometer, would identify the density of the solid materials formingthe powder and the particles according to the equation:

ρ=P/V(g/cc)

but rather to refer to the apparent density (in some documents by othersdescribed as “envelope density”) of the particle, considering itsoverall volume.

Given the technical difficulty of measuring this overall volume for eachsingle particle, the cited patent applications have referred to volume(and subsequently to density) parameters of the powder as bulk volumeand tapped volume.

The patent application WO 03/0350030 A1 describes the preparation of akit for inhalation administration that considers the preparation of asolid dry form containing a drug prepared by freeze-drying a solution.The process, also described through examples, presents greatdifficulties in relation to industrial production and, above all,provides no guarantees of substantial improvement of the stability ofthe active agent over time. In fact, after freeze-drying the drug addedto the formulation is dispersed in an excipient network characterized byhigh porosity that cannot be modulated or modified through the process.Although it is useful from the point of view of rapid dissolution of thesolid form, this porosity increases exposure of the drug to atmosphericagents and compromises its stability. In the specific case, no data areprovided on the porosity of the freeze-dried products obtained in theexamples, but literature data obtained through indirect measurementsplace the apparent density (corresponding to the bulk density of apowder) of formulated freeze-dried tablets containing sugars andsurfactants between 0.05 and 0.2 g/cc.

The patent application CA2536319 describes a pharmaceutical compositionobtained by spray drying, with a moisture content below 1%. According towhat is indicated, this very low moisture content is necessary to ensurethe stability of the composition, as a water content of over 1% in theformulation would cause degradation of the pharmacologically activesubstances, resulting in a loss of efficacy of the composition. Toreduce the level of moisture the composition is constituted by a largeamount of mannitol, which however compromises the physical features ofthe powder considerably, increasing the particle size and decreasing thedose of powder delivered from the mouthpiece of the inhalation deviceused.

The problem of producing inhalation powders with high dispersibility hasbeen solved through the engineering of particles that contain the drugas dispersed as possible.

Briefly, the technique used is that of producing essentially fineparticles (geometric mean diameter greater than 4.0 μm) consisting ofsmall amounts of active agent dispersed at molecular level inside anappropriate matrix of excipients capable of guaranteeing, through thespray-drying preparation technique, the formation of a low densitycoarse particle.

This formulation approach requires the use of high percentages ofexcipients in the formulation, but enables small amounts of active agentto be contained in the composition.

For this reason, although these compositions solve the problem ofaerodynamic performance, they fail to solve significant questions interms of chemical stability.

The production of an inhalation powder in which the content % of activeagent is high using a spray-drying technique must instead be consideredadvantageous in terms of chemical stability. Considering the commonactive agents of respiratory therapy, in the majority of cases thiscontent % of active agent would be too high to allow the production ofan inhalation powder form, given the limited amount of powder thatconstitutes an individual dose of product.

In fact, this amount of powder is too small to be dosed reproducibly byany industrial device for producing individual doses of inhalationpowders.

Therefore, the production of an inhalation powder that is stable bothfrom a chemical and physical point of view must necessarily reconcilethe need for stability of the active agents used with the need to ensureadequate aerosol performance in terms of deposition in the deep lung.

From the point of view of chemical stability, an ideal approach isrepresented by the production of dry powders containing large amounts ofactive agent in combination with a sugar capable of decreasing molecularmobility in the particles of powder and a hydrophobic excipient capableof limiting interaction with the external environment and absorption ofwater by the powder.

From the point of view of aerosol performance, the same powder must becharacterized by an adequate particle diameter for inhalationadministration and by a composition capable of facilitating particledisaggregation at the time of inhalation.

At the same time, convergence of physical composition features of thepowder must coincide with the ability to divide the powder evenly usingdevices for the industrial preparation of products in the form ofinhalation powder in individual doses or of multidose inhalers capableof drawing a relatively large dose from a storage chamber containedtherein.

Normally, in order to reproducibly deliver inhalation powders in anindividual dose, carriers and inert fillers are used to enable rapid andefficient dilution of the active agent so that it can be easily meteredin inhalers.

Lactose has been used as carrier in powder inhalation formulations (drypowder inhalers—DPI) since it was introduced in 1948 in the Aerohalerinhaler by Abbott.

In fact, lactose represents the only approved carrier for powderinhalation formulations and is used to produce homogeneous formulationsin combination with micronized active agents facilitating divisionaccuracy even the case of extremely small doses.

Inhalation formulations in powder form are generally produced asmixtures of coarse carrier particles combined with micronized particlesof active agents generally with an aerodynamic diameter from 1-5 um.

Carrier particles are used to increase the flow of the particles ofdrug, thereby improving division accuracy and reducing variability ofthe dose observed in formulations containing only the active agent. Withthis formulation approach, it is possible to increase the size of thedose of powder to be handled, which otherwise would not exceed 1 mgtotal of active agent, facilitating handling and division of the bulkpowders during production operations.

With the use of carrier particles, the particles of drug are emittedfrom the inhaler (single or multi-dose) more readily and therefore alsothe delivery efficiency of the powder is increased.

The presence of a coarse carrier such as lactose also provides thepatient with feedback during the inhalation phase, since it deposits onthe taste buds and produces a blandly sweet sensation, confirming thatthe dose of drug has been taken correctly. Consequently, the lactosecarrier represents an important component of the formulation and anychanges to it in chemical and physical terms have the potential to alterthe lung deposition profile of the drug. Therefore, the design of thecarrier particles is important in the development of inhalation powderformulations.

During inhalation, the particles of drug adhering to the surface of thecarrier particles detach as a result of the energy of the inhaled airflow that overcomes the adhesion forces between drug and carrier. Thecoarse particles of the carrier impact in the upper airways while thesmaller particles of drug move through the lower airways and aredeposited in the deep lung.

Insufficient detachment of the drug particles from those of the carrierdue to strong interparticle energies must be considered the main causeof inefficient lung deposition of many powder inhalation products.Therefore, an effective inhalation formulation should be producedidentifying the correct balance between adhesive and cohesiveinterparticle forces so as to guarantee sufficient adhesion betweenmicronized drug and coarse lactose carrier to provide a stableformulation (with homogeneous mixtures and without segregation ofpowders and suitable uniformity of content) as well as guaranteeingefficacious detachment of the drug from the carrier during inhalation.

Consequently, the efficiency of a powder formulation depends greatly onthe properties of the carrier and its selection is a key element for thegeneral performance of the inhalation product. The range of materialsthat can be proposed for use as carrier in inhalation pharmaceuticalproducts is extremely limited for toxicological reasons. Lactose andother sugars have been studied and used and consequently certainmodifications of these materials can guarantee further formulationoptimizations.

Various and controversial reports have been published regarding the mostsuitable sizes for a carrier for inhalation use. Some studies reportimprovements in the amounts of respirable drug delivered by a powderinhaler obtained through reducing the sizes of the carrier particles. Ithas been proposed that certain small agglomerates are more sensitive toturbulent motion in the inhaled air flow, causing more efficientdeagglomeration. However, the use of a carrier that is too small causesa worsening in the flow properties of the powder, which is also one ofthe main reasons for incorporating a coarse carrier in the formulation.On the other hand, it has been reported that carrier particles that aretoo large normally exhibit larger surface discontinuities, than finecrystals. This can have the advantage of offering protection to theparticles of active agent, preventing detachment during the mixing step.Therefore, a large particle size of the carrier is not necessarily anegative element from the point of view of drug deposition afterinhalation. Thus, formulations with coarse carriers generally exhibit abetter dispersion of the drug than similar formulations obtained withcarrier particles of small size. This is due to weaker interparticleforces in the case of particles of larger sizes.

Even if the influence of the shape of the carrier particles on thedispersibility of the drug of a powder inhalation formulation is notwell defined, it is known that the attractive forces between drug andcarrier particles can depend on the morphology, in fact the mostcommonly used particles for powder inhalation formulations haveirregular morphology.

In the light of all of the aforesaid considerations, it would beadvantageous to be able to produce a pharmaceutical composition forinhalation use in the form of dry powder that is stable and easy toadminister with common dispensers for inhalation powders, whileremaining easy to produce. It would also be advantageous to obtain asolid composition in the form of dry powder, which can be used asdiluent of inhalation powders in order to enable correct mixing ofpowders containing different active agents also in small amounts and atthe same time maintains high stability of the formulation, preventingdegradation of the active agents.

However, the problem of providing an inhalation formulation of drugsthat is stable and administrable with common dispensers of inhalationpowders, with features of high deliverability and respirability, andwhich can be produced with a commercially viable process, currentlyremains unsolved or unsatisfactorily solved.

Therefore, a first aspect of the present invention is to provide apharmaceutical composition for inhalation use in powder form,comprising:

-   -   a) a first powder comprising at least a powder (a₁) comprising        an active agent or a pharmaceutically acceptable salt thereof,        in an amount greater than 1% by weight of said powder, leucine        in an amount from 5 to 70% by weight of said powder, a sugar in        an amount from 20 to 90% by weight of said powder;    -   b) a second powder comprising a mixture of a first lactose which        has an X50 from 35 to 75 μm, with a second lactose which has an        X50 from 1.5 to 10 μm, the content of said first and second        lactose in said mixture being respectively from 85% to 96% and        from 4% to 15%,        wherein the ratio by weight between the first and the second        powder included in the pharmaceutical composition is from 1/5 to        1/100.

The composition also has a fine particle fraction (FPF) greater than 60%and a delivered fraction (DF) greater than 80%.

A further aspect of the invention is represented by a Kit foradministration of a drug as inhalation powder, comprising a meteredamount of the composition according to the present invention and aninhalation device.

In a further embodiment of the pharmaceutical composition according tothe present invention, the third powder (a₂) comprises a powder(hereinafter also defined as bulking agent) comprising leucine in anamount from 5 to 70% by weight of said second powder, a sugar in anamount from 20 to 90% by weight of said second powder.

With a pharmaceutical composition as described in this secondembodiment, it is possible to obtain a pharmacologically activecomposition that can comprise an active agent that must be dosed in verysmall amounts both maintaining the ratio between first and second powderof the composition unchanged and guaranteeing high respirability.

In a further embodiment of the pharmaceutical composition according tothe present invention, the first powder comprises a fourth powder (a₃)comprising an active agent, in an amount greater than 1% by weight ofsaid third powder, leucine in an amount from 5 to 70% by weight of saidthird powder, a sugar in an amount from 20 to 90% by weight of saidthird powder.

With a pharmaceutical composition as described in this third embodiment,it is possible to obtain a pharmacologically active composition that cancomprise the combination of two or more different active agents capableof acting synergically, or simply acting simultaneously in the site ofapplication, so as to reduce the number of administrations.

According to the present invention, the term “active agent” is intendedas any substance with a desired biological therapeutic efficacy.

Examples of active agents that can be administered by inhalationcomprise: β2 agonists; steroids such as glucocorticosteroids orcorticosteroids (preferably anti-inflammatory agents); anti-cholinergicagents; leukotriene antagonists; inhibitors of leukotriene synthesis;mucolytics; antibiotics, pain relievers in general such as analgesic andanti-inflammatory agents (including steroid and non-steroidanti-inflammatory agents); cardiovascular agents such as glucosides;respiratory agents; anti-asthma agents; short and long actingbronchodilator inhalers; anti-cancer agents; alkaloids (i.e. rye ergotalkaloids) or triptans such as sumatriptan or rizatriptan that can beused to treat migraine; agents (i.e. sulfonylurea) used to treatdiabetes and related dysfunctions; sleep inducing drugs such as sedativeand hypnotic agents; psychic energizers; appetite inhibitors;anti-arthritis agents; anti-malaria agents; anti-epileptic agents;anti-thrombotic agents; anti-hypertensive agents; anti-arrhythmicagents; anti-oxidant agents; anti-psychotic agents; anxyolitics;anti-convulsant agents; anti-emetic agents; anti-infective agents;anti-histamines; anti-fungus and anti-viral agents; drugs to treatneurological dysfunctions such as Parkinson's disease (dopamineantagonists); drugs to treat alcoholism and other forms of addiction;drugs such as vasodilators to treat erectile dysfunction; musclerelaxants; muscle contractors; opioids; stimulating agents;tranquilizers; antibiotics such as macrolides; aminoglycosides;fluoroquinolones and β-lactames; vaccines; cytokines; growth factors;hormones including birth-control drugs; sympathomimetic agents;diuretics; lipid regulating agents; anti-androgen agents;anti-parasitics; blood thinners; neoplastic agents; anti-neoplasticagents; hypoglycemic agents; nutritional agents and supplements; growthsupplements; anti-enteric agents; vaccines; antibodies; diagnostic andcontrast agents; or mixtures of the above substances (e.g. combinationsfor the treatment of asthma containing steroids and β-agonists); heparinand its derivatives such as heparins with molecular weight from 15 to 30Kda and semi-synthetic heparin derivatives; substances with antioxidantaction such as N-acetylcysteine, Carnosine, Melatonin, Resveratrol,Ascorbic Acid, Alpha-tocopherol, Folic Acid, Trans-caffeic Acid,Hesperidin, Epigallocatechin-gallate, Delphinidin, Rosmarinic Acid,Myricetin, 5-methyltetrahydrofolic acid, 5-formyltetrahydrofolate acid,5-formyl tetrahydrofolic acid, Astaxanthin, Lycopene, Curcumin,Pinostilbene, Pterostilbene and Isorhapontigenin.

The aforesaid active agents belong to one or more structural classes,including, but not limited to, small molecules (preferably smallinsoluble molecules), peptides, polypeptides, proteins, polysaccharides,steroids, nucleotides, oligonucleotides, polynucleotides, fats,electrolytes and the like.

Specific examples include the β2-agonists salbutamol, salmeterol (i.e.salmeterol xinafoate), formoterol and formoterol fumarate, fenoterol,indacaterol, olodaterol, vilanterol, levalbuterol and carmoterol,steroids such as beclomethasone dipropionate, budesonide and fluticasone(e.g. fluticasone proprionate or fluticasone furoate), ciclesonide,mometasone furoate, anti-cholinergics such as glycopyrronium bromide,aclidinium bromide, umeclidinium, ipratropium bromide, oxitropium,tiotropium bromide;

With regard to peptides and proteins, the present invention alsocomprises synthetic, recombinant, native, glycosylated andnon-glycosylated peptides and proteins and biologically active fragmentsand analogs.

Active agents for which an immediate release into the bloodstream isparticularly advantageous to obtain a rapid pharmacological effectinclude those to be used to treat migraine, nausea, insomnia, allergicreactions (including anaphylactic reactions), neurological andpsychiatric disorders (in particular panic attacks and other psychosesor neuroses as well as Parkinson's disease), among these active agents,levodopa and monoamine oxidase inhibitors including safinamide, erectiledysfunction, diabetes and related diseases, heart diseases,anti-convulsive agents, bronchodilators and active agents to treat painand inflammation. According to the present invention, vaccinesconstituted by antibodies, cells, corpuscles and cellular portions canalso be administered.

Other examples of active substances are steroids and their salts, suchas budesonide, testosterone, progesterone, flunisolide, triamcinolone,beclomethasone, betamethasone, dexamethasone, fluticasone,methylprednisolone, prednisone, hydrocortisone and the like; peptidessuch as cyclosporine and other water-insoluble peptides; retinoids suchas cis-retinoic acid, 13-trans-retinoic acid and other derivatives ofvitamin A and of beta-carotene; vitamins D, E and K and their precursorsand water-insoluble derivatives; prostaglandins, leukotrienes and theiractivators and inhibitors including prostacyclin, prostaglandins E1 andE2, tetrahydrocannabinol, pulmonary surfactant lipids; lipid-solubleanti-oxidants; hydrophobic antibiotics and chemotherapic drugs such asamphotericin B, adriamycin and the like.

A further example of active substance is pirfenidone, employed in thetreatment of idiopathic pulmonary fibrosis.

In particular, according to the present invention the active agent is ahydrolyzable active agent, i.e. a substance capable of undergoingdegradation processes as a function of the amount of water present inthe formulation.

According to the present invention, the term “sugar” is intended asmonosaccharides with 5 or more carbon atoms, disaccharides,oligosaccharides or polysaccharides and also polyols with 5 or morecarbon atoms (often also defined as sugar-alcohol)

Examples of sugars that can be administered by inhalation comprise:lactose, trehalose, sucrose, maltose, melibiose, cellobiose, mannitol,dextrins, maltodextrins, sorbitol, galactitol, iditol, volemitol,fucitol, inositol, maltitol, lactitol, isomalt, maltotriose,maltotetraose, polyglycitol.

The amount of sugar present in the powders (a₁, a₂, a₃) contained in thefirst powder of the pharmaceutical composition of the presentdescription is from 20 to 90% by weight of each powder, preferably in anamount from 20 to 80% by weight of each powder, even more preferably inan amount from 40 to 80% by weight of each powder.

According to the present invention the powders (a₁, a₂, a₃) contained inthe first powder of the pharmaceutical composition of the presentdescription include a hydrophobic substance to reduce moisturesensitivity. This hydrophobic substance is leucine, which alsofacilitates particle disaggregation. Leucine is present in an amountfrom 5 to 70% by weight of each powder, preferably in an amount from 15to 70% by weight of each powder, even more preferably in an amount from18 to 55% by weight of each powder.

According to the present invention, the powders (a₁, a₂, a₃) containedin the first powder of the pharmaceutical composition of the presentdescription include a surfactant in an amount from 0.2 to 2.0% by weightof each powder, preferably in an amount from 0.4 to 0.8% by weight ofeach powder.

The surfactant of the pharmaceutical composition according to theinvention can be selected from the various classes of surfactants forpharmaceutical use.

Surfactants suitable to be used in the present invention are all thosesubstances characterized by medium or low molecular weight containing ahydrophobic moiety, generally readily soluble in an organic solvent butweakly soluble or totally insoluble in water, and a hydrophilic (orpolar) moiety, weakly soluble or completely insoluble in an organicsolvent but readily soluble in water. Surfactants are classifiedaccording to their polar moiety. Therefore, surfactants with anegatively charged polar moiety are called anionic surfactants, whilecationic surfactants contain a positively charged polar moiety.Uncharged surfactants are generally called non ionic, while surfactantswith both a positive and negative charge are called zwitterionic.Examples of anionic surfactants are represented by the salts of fattyacids (better known as soaps), sulfates, sulfate ethers and phosphateesters. Cationic surfactants are frequently based on polar groupscontaining amino groups. The most common non ionic surfactants are basedon polar groups containing oligo-(ethylene-oxide) groups. Zwitterionicsurfactants are generally characterized by a polar group constituted bya quaternary amine and a sulfuric or carboxylic group.

Specific examples of this application are represented by the followingsurfactants: benzalkonium chloride, cetrimide, docusate sodium, glycerylmonooleate, sorbitan esters, sodium lauryl sulphate, polysorbates,phospholipids, bile salts.

Non ionic surfactants, such as polysorbates and polyoxyethylene andpolyoxypropylene block copolymers, known as “Poloxamers”, are preferred.Polysorbates are described in the CTFA International Cosmetic IngredientDictionary as mixtures of sorbitol and sorbitol anhydride fatty acidesters condensed with ethylene oxide. Particularly preferred are nonionic surfactants of the series known as “Tween”, in particular thesurfactant known as “Tween 80”, a polyoxyethylene sorbitan monooleateavailable on the market.

The presence of a surfactant, and preferably of Tween 80, is necessaryto reduce the electrostatic charges found in formulations without it,flow of the powder and maintenance of a homogeneous solid state withoutinitial crystallization.

According to the present invention, the term “inhalable” is intended asa powder suitable for pulmonary administration. An inhalable powder canbe dispersed and inhaled by means of an appropriate inhaler, so that theparticle can enter the lungs and alveoli to provide the pharmacologicalfeatures of the active agent of which it is formed. A particle withaerodynamic diameter of less than 5.0 μm is normally consideredinhalable.

The term “amorphous” according to the present invention is intended as apowder that contains less than 70% of crystalline fraction, morepreferably less than 55%. The pharmaceutical composition described inthis text has a ratio between the amount of powder in amorphous formthat constitutes the composition expressed by weight and the amount ofsugar present in the composition expressed by weight ranging from 0.8 to2.0. This ratio indicates that the sugar present in the powder is asubstantially amorphous sugar, which therefore has a crystallinefraction of less than 50%. This enables the sugar to coordinate thewater present in the composition, preventing it from being available tohydrolyze the active agent, thereby making it ineffective.

The term “fine particle fraction (FPF)” is intended as the fraction ofpowder, with respect to the total delivered by an inhaler, which has anaerodynamic diameter (dae) of less than 5.0 μm. The term “deliveredfraction (DF)” is intended as the fraction of active agent delivered,with respect to the total loaded. The characterization test that isperformed to evaluate these properties of the powder is the Multi StageLiquid Impinger (MSLI) test, as described in the European Pharmacopoeiacurrent ed. The conditions for performing this test consist insubjecting the powder to an inhalation through the inhaler such as togenerate a flow of 60±2 liters/min. This flow in the case of the ModelRS01 Inhaler (Plastiape, Osnago, IT) is obtained by generating apressure drop of 2 KPa in the system.

The preferred production process of the powder or powders constitutingthe first powder according to the invention is spray drying startingfrom a solution of leucine, of a sugar and a surfactant in which thedrug, if present, is dissolved or dispersed as suspension or emulsion.

The preferred particle size for this first powder provides that at least50% of the size distribution (X50) is below 5 μm, preferably below 3 μm,more preferably below 2.0 μm, also to increase the surface areaoptimizing deep lung deposition.

According to the present invention, the powder or powders thatconstitute the first powder of the pharmaceutical composition accordingto the present description is a substantially dry powder, i.e. a powderwith a moisture content of less than 10%, preferably less than 5%, morepreferably below 3%. This dry powder preferably has no water capable ofhydrolyzing the active agent making it inactive. The amount of moisturepresent in the composition is controlled by the presence of leucine,which limits the content due to its hydrophic features, both in the stepto produce the powder and in the subsequent handling steps, and ofsugar, which traps the water in a structure that becomes increasinglyrigid over time, preventing the water from hydrolyzing the active agent.

According to the present invention the second powder included in thepharmaceutical composition for inhalation use comprises a mixture of twotypes of lactose with different particle size. With this powder it ispossible to obtain a composition that can be easily divided in the meansused for administration, such as the capsules used in inhalationsystems, and at the same time obtain a composition with highrespirability so that the active agent or agents used can be depositedin deep lung regions and perform their pharmacological action.

According to what is described above, a composition comprising a secondlactose powder that is too fine or too coarse is not an ideal solutionfor obtaining the respirability results desired. Therefore, thepossibility of adding an amount of fine particles of lactose toformulations of inhalation powders already containing coarse lactosepowders in order to improve the inhalation efficiency of drugs wasevaluated.

Studies conducted confirmed that the presence of fine lactose wellassociated with coarser lactose is capable of performing a key role inthe drug dispersion process. In a preferred embodiment, the addition ofaround 10% of fine lactose mixed with coarse lactose showed that thefine component helps the particles including the active agent to detachfrom the coarse particles. It was also reported that the concentrationof fine lactose added must be carefully controlled since the desireddispersibility of the drug can be reached without substantiallyinfluencing the flow properties of the drug. On the contrary, thepresence of an excess of fine lactose tends to inhibit flow of thepowder since this can enter the voids between the larger particles andpromote compacting and consequent thickening of the powder. It was alsoreported that the presence of an excess of fine lactose causes adecrease of the respirable fraction of an inhalation powder.

According to the present invention, the mixture comprises a lactose withlarger particle size, i.e. with an X50 (at least 50% of the particles)from 35 to 75 μm present in an amount greater than a second lactose withsmaller particle size, i.e. with an X50 from 1.5 to 10 μm. Inparticular, the lactose with larger particle size is present in themixture in a percentage by weight of the mixture from 85 to 96%, whilethe lactose with smaller particle size is present in the mixture in apercentage by weight of the mixture from 4 to 15%. Preferably, thelactose with larger particle size is present in the mixture in apercentage by weight of the mixture from 91 to 95%, while the lactosewith smaller particle size is present in the mixture in a percentage byweight of the mixture from 5 to 9%.

In order to obtain a composition having properties of highrespirability, the particles of the first powder constituting thepharmaceutical composition must be in an amount that ensures easydetachment thereof from the lactose particles that form the secondpowder. Therefore, the ratio between the first and the second powdercomprising the mixture of lactoses must be from 1/100 to 1/5. This ratioprovides the composition with high respirability, guaranteeing goodpharmacological response of the active agent.

For some active agents, whose doses in the pharmaceutical composition tobe administered are very low and consequently insufficient to ensure anadequate ratio between first and second powder, the first powder alsocomprises an inert powder from a pharmacological point of view capableof increasing the amount of first powder with respect to the secondpowder so as to guarantee an aerodynamic performance that allows theactive agent to reach the site of action.

The process for preparing the pharmaceutical composition according tothe invention substantially comprises the operations of:

-   -   a) providing a first powder comprising at least a powder        obtained by spray drying comprising an active agent in an amount        greater than 1% by weight of the powder, leucine in an amount        ranging from 5 to 70% by weight of the powder, a sugar        substantially amorphous after obtaining the powder by spray        drying in an amount ranging from 20 to 90% by weight of the        powder;    -   b) providing a second powder obtained by mixing a first lactose        which has an X50 from 35 to 75 μm, with a second lactose which        has an X50 from 1.5 to 10 μm, the content of the first and        second lactose in the mixture being respectively from 85% to 96%        and from 4% to 15%,    -   c) mixing the powders.

In particular, the production process of the composition, in step a) ofobtaining the powder or powders by spray drying, consists of a series ofoperations illustrated below:

For step a):

-   -   preparing a first phase (A) in which an active agent is present        in an appropriate liquid medium;    -   preparing a second phase (B) in which the leucine, the sugar and        surfactants are dissolved or dispersed in an aqueous medium;    -   mixing said phases (A) and (B) to obtain a third phase (C) in        which the liquid medium is homogeneous;    -   drying said phase (C) in controlled conditions to obtain a dry        powder with particles having a size distribution with median        diameter of less than 10.0 μm;    -   collecting said dry powder.

Phase (A) can be either a suspension of the active agent in an aqueousor non aqueous medium, or a solution of the active agent in anappropriate solvent.

Preparation of a solution is preferable, and the organic solvent isselected from those soluble in water. In this case, phase (C) is also asolution of all the components of the desired composition.

Instead, when phase (A) is a suspension of the hydrophobic active agentin an aqueous medium, phase (C) is also a suspension in an aqueousmedium, which will contain the dissolved soluble components such as theexcipients and surfactants.

The drying operation consists of eliminating the liquid medium, solventor dispersant, from phase (C), to obtain a dry powder with the desireddimensional features. This drying is preferably obtained byspray-drying. The features of the nozzle and the process parameters areselected so that the liquid medium is evaporated from the solution orsuspension (C) and a powder with the desired particle size is formed.

The production process of the composition, in step b) of obtaining themixture of lactose, consists of physical mixing of lactoses withdifferent particles sizes obtained according to normal mixingtechniques. In a preferred embodiment of the invention, the lactosesused are Respitose® SV003 (DFE Pharma, Goch, D) and Lacto-Sphere® MM3(Microsphere SA, Ponte Cremenaga, Lugano CH).

Step c) of the process for preparing the pharmaceutical compositioninstead consists of physical mixing of the powders obtained by spraydraying and of the lactose mixture using the most common mixingtechniques, i.e. rotating mixers such as Turbula, V-mixer, cylinder,double cone, cube mixers or stationary mixers used only for mixing, suchas planetary, nautamix, sigma, ribbon mixers or mixer-granulators, suchas Diosna. Besides these mixers, the powders could also be mixed withdevices normally used to mix liquids, such as Ultra Turrax or Silversonand, ultimately, also inside fluid bed granulation apparatus.

As already indicated above, the first powder constituting thepharmaceutical composition according to the present invention cancomprise a powder, called bulking agent (BA), comprising leucine in anamount from 5 to 70% by weight of the powder; a sugar in an amount from20 to 90% by weight of the powder, in which the composition has a fineparticle fraction (FPF) greater than 60% and a percentage of the dosedelivered from the mouthpiece (DF) greater than 80%.

This composition can be used to increase the amount of the first powderwith respect to the second powder comprising the mixture of lactoseguaranteeing the correct ratio between the two powders, maintainingproperties of high respirability of the composition according to theinvention.

The production process of the bulking agent is substantially similar tothe process for preparing the powder containing the active agent (stepa), in particular, this process consists of the following operations:

-   -   preparing a first phase (A) in which the leucine, the sugar and        surfactants are dissolved or dispersed in an aqueous medium;    -   drying said phase (A) in controlled conditions to obtain a dry        powder with particles with a size distribution having a median        diameter of less than 10.0 μm;    -   collecting said dry powder.

EXAMPLES

The methods for preparing the powders that constitute the pharmaceuticalcomposition and for preparing the solid composition for use as diluent(hereinafter bulking agent) of the present invention will now bedescribed.

Preparation of the Individual Powders.

The powders containing the active agents and the bulking agent wereobtained by spray drying, a drying technique used to obtain powders withuniform and amorphous particles from solutions of active agents andexcipients in appropriate solvent or mixture of solvents.

For the formulations described the solvents used are water and ethylalcohol in a fixed ratio of 70/30. The concentration of dissolved solidsis 1% w/v for formulations containing the active agent and 2% w/v forthe bulking agent.

In the case of the powder containing as active agent FormoterolFumarate, tiotropium bromide and bulking agent, all the components ofthe powder were dissolved in water and the solution thus obtained wasadded to the portion of ethyl alcohol slowly at 25° C., taking care notto cause precipitation of some of the components.

For the formulation containing Budesonide as active agent, the activeagent was dissolved separately in the alcohol portion to which theaqueous solution of the excipients was added to obtain a singlewater-alcohol solution.

The water-alcohol solution thus obtained was processed by means of aBuchi Mod. B290 spray dryer, using an open cycle with the followingparameters:

-   -   nozzle diameter 0.7 mm    -   atomization gas nitrogen    -   atomization pressure 4 bar    -   drying gas air    -   aspiration 100% (35 m3/h)    -   inlet temperature 170° C.    -   feed speed 8% (2.4 ml/min)

Powder collection system: cyclone separator with glass collection vessel

Outlet filter: polyester sleeve.

At the end of the drying process the powder collection step wasperformed in controlled temperature and humidity conditions: temperature<25° C., relative humidity <35%.

The powders were packaged immediately after production in borosilicateglass vials inserted in a double aluminum foil bag heat-sealed underpartial vacuum (30%).

Storage Conditions for Accelerated Stability Study.

The powders produced by spray drying, divided and packaged inborosilicate glass vials sealed inside in a double aluminum foil bagheat-sealed under partial vacuum (30%) were stored for an acceleratedstability study in an oven at a temperature of 40° C. and relativehumidity of 13%.

At each time interval established by the study, the samplescorresponding to the stability point were taken, left to cool untilreaching room temperature, opened in controlled conditions in a glovebox (temperature<20° C., RH<35%) and analyzed as established in theprotocol.

Characterization of the Powder: Particle Size Analysis.

The powders obtained after spray drying were characterized in terms ofdry particle size using a Sympatec Helos light scattering device thatanalyzes the particle size according to the Fraunhofer theory andequipped with RODOS disperser.

The instrument was suitably calibrated with reference material andprepared following the instructions provided in the instrument usermanual.

After appropriate cleaning before analysis, an amount of powder for eachbatch produced was analyzed without any preliminary preparation of thesample.

The dispersion gas used was compressed air suitably cleansed ofparticles.

The test method specified therefore provides for compliance with thefollowing measures in relation to the sample, to the powder disperserand to the light scattering analyzer.

Sample

-   -   size: about 100 mg    -   feed procedure: with a spatula    -   pre-treatment of the sample: none

RODOS Disperser

-   -   Model M ID-NR 230 V/Hz 24Va    -   Dispersion pressure: 3 bar

Light Scattering Analyzer

-   -   Model: Helos    -   Test method: Fraunhofer    -   Software version: Windox 4.0    -   Test lens: R1 (0.1-35 μm)    -   Minimum optical concentration: 1%    -   Activation threshold: minimum optical concentration detectable        1% for max 30 seconds of time and with at least 100 ms of        exposure of the sample.

All the tests were conducted in controlled temperature and humidityenvironments, temperature <25° C. and relative humidity <50% RH.

Size analysis provides volume median diameter (VMD) values of thepopulation of particles in the sample of powder.

Characterization of the Powder: Residual Moisture Content.

The residual moisture content in the powder obtained by spray drying wasmeasured using the Karl Fischer coulometric system method.

The C20 Compact Karl Fischer Coulometer Mettler Toledo titrator was usedfor this purpose, which uses as reagent HYDRANAL®-Coulomat AG.

The sample powders were accurately weighed in an amount of around 15-20mg and the weight was recorded in the parameters of the sample.Titration was started immediately after adding the sample to the reagentbath.

At the end of the test, the instrument indicates directly the percentageof water contained in the sample.

Characterization of the Powder: Determination of Titer and Related.

Three different HPLC (High Performance Liquid Chromatography) methodswere used to determine the content of active agents in samples from MSLItests and in the formulations, as well as of their related substances,as set down below:

-   Method 1: Determination of formoterol and budesonide in MSLI samples    -   Determination of the titer of formoterol and budesonide    -   Determination of the degradation products of formoterol and        budesonide-   Method 2: Determination of tiotropium in MSLI samples (also in the    presence of formoterol and/or budesonide)-   Method 3: Determination of the tiotropium titer (also in the    presence of formoterol and/or budesonide)    -   Determination of the degradation products (also in the presence        of formoterol and/or budesonide)

Method 1

The test method used to determine the content in MSLI samples, titer anddegradation products for formulations containing Formoterol/Budesonide,is characterized by the following parameters:

Solvent: 50/50 methanol/phosphate buffer pH 2.7 25 mM

Mobile phase: acetonitrile/phosphate buffer pH 2.9 2.82 mM

-   -   gradient elution

Time % buffer Flow (min) % ACN pH 2.9 (ml/min) 0 22 78 0.5 2.5 22 78 0.53.0 41 59 0.7 8.0 41 59 0.7 10.0 70 30 0.7 12.0 22 78 0.6 15.0 22 78 0.6

Injection volume: 20 μL

Analysis column: Agilent Poroshell 120 EC-C18, 100 mm×3.0 mm, 2.7 μm

Column temperature: 30° C.

Wavelength: 220 nm (Formoterol Fumarate) and 240 nm (Budesonide)

Retention time: 2.4 min (Formoterol Fumarate) and 8.0 min (Budesonide)

An HPLC Agilent model 1200 with diode array type detector, model G1315Cwas used for the test.

The samples for analysis were obtained by dissolving in the solvent anamount of powder such as to obtain a concentration of 160 μg/ml for theBudesonide and 4.5 μg/ml for the Formoterol Fumarate, as for thereference solution.

The reference solution was injected three consecutive times before thesample to determine the precision of the system expressed as relativestandard deviation percentage (RSD %), which must be less than 2%.

The active agent content is obtained by calculating the ratio of theareas with respect to the reference solution at known concentration. Thedegradation of the product is calculated as ratio between the sum of theareas of all the analysis peaks corresponding to the degradationproducts and the active agent taken as reference. All the analysis peakswhose chromatogram area was greater than 0.1% of the area of the activeagent are counted in the sum of the degradation products.

Method 2

The test method used to determine the Tiotropium content in MSLIsamples, alone or in combination with Formoterol and/or Budesonide, ischaracterized by the following parameters:

Solvent: 40/60 methanol/phosphate buffer pH 2.7 25 mM

Mobile phase: acetonitrile/phosphate buffer pH 2.9 2.82 mM

-   -   gradient elution

Time % buffer Flow (min) % ACN pH 2.9 (ml/min) 0 22 78 0.5 2.9 22 78 0.53.3 22 78 1.0 4.0 22 78 1.0 4.1 41 59 0.7 9.0 41 59 0.7 11.0 80 20 0.613.0 22 78 0.6 16.0 22 78 0.6

Injection volume: 20 μL

Analysis column: Agilent Poroshell 120 EC-C18, 100 mm×3.0 mm, 2.7 μm

Column temperature: 30° C.

Wavelength: 220 nm (Formoterol Fumarate) and 240 nm(Tiotropium-Budesonide)

Retention time: 2.3 min Formoterol Fumarate; 3.5 min Tiotropium; 9.0 minBudesonide.

An HPLC Agilent model 1200 with diode array type detector, model G1315Cwas used for the test.

The reference solution was injected three consecutive times before thesample to determine the precision of the system expressed as relativestandard deviation percentage (RSD %), which must be less than 2%.

The active agent content is obtained by calculating the ratio of theareas with respect to the reference solution at known concentration.

Method 3

The test method used to determine the titer and degradation products forformulations containing Tiotropium is characterized by the followingparameters:

Solvent: 40/60 methanol/phosphate buffer pH 2.7 25 mM

Mobile phase: acetonitrile/phosphate buffer pH 2.9 2.82 mM

-   -   gradient elution

Time % buffer Flow (min) % ACN pH 2.9 (ml/min) 0 20 80 0.7 6 20 80 1.015 25.6 74.4 1.0 15.5 25.6 74.4 1.2 18 32 68 1.2 25 40 60 1.2 28 60 401.2 29 60 40 1.4 33 70 30 1.4 35 70 30 0.7 40 20 80 0.7 60 20 80 0.7

Injection volume: 20 μL

Analysis column: Agilent Poroshell 120 EC-C18, 150 mm×4.6 mm, 2.7 μm

Column temperature: 30° C.

Wavelength: 240 nm-Tiotropium; 315 imp.F Tiotropium.

Retention time: 9 min Tiotropium;

An HPLC Agilent model 1200 with diode array type detector, model G1315Cwas used for the test.

The samples for analysis were obtained by dissolving in the solvent anamount of powder such as to obtain a concentration of 6 μg/ml forTiotropium Bromide, as for the reference solution.

The reference solution was injected three consecutive times before thesample to determine the precision of the system expressed as relativestandard deviation percentage (RSD %), which must be less than 2%.

The content in active agents is obtained by calculating the ratio of theareas with respect to the reference solution at known concentration. Thedegradation of the product is calculated as ratio between the sum of theareas of all the analysis peaks corresponding to the degradationproducts and the active agent taken as reference. All the analysis peakswhose chromatogram area was greater than 0.1% of the area of the activeagent are counted in the sum of the degradation products.

Characterization of the Powder: Differential Scanning Calorimetry.

Differential scanning calorimetry or DSC is a thermoanalytical techniqueused to determine chemical and physical phenomena with endothermic orexothermic effect in a sample, such as variations in phase, loss ofwater, chemical reactions.

In DSC the sample is heated with constant heating speed and the amountof heat required to raise its temperature is a function of its thermalcapacity. Each endothermic or exothermic phenomenon causes a reversibleor irreversible change in the thermal capacity of the material and canbe detected as a variation of the baseline of the thermogram.

Formulations containing amorphous lactose show during heating a typicaldecrease in thermal capacity corresponding to the glass transition ofthe lactose from amorphous solid state to a metastable state thatrapidly leads to its crystallization, characterized by an exothermicpeak.

The temperature corresponding to these phenomena varies as a function ofthe composition of the sample and of the environmental conditions inwhich the sample is stored and prepared.

The samples were prepared in a controlled environment (temperature <20°C., relative humidity 35-30%). 40 uL aluminum standard crucibles for DSCwere filled with a weighed amount of powder between 1 mg and 3 mg andsealed with specific lid.

Calorimetry testing of the samples in question was carried out bysubjecting the samples to a heating ramp from 20 to 200° C. with atemperature increase of 10° C./min.

The test gives a thermogram in which the thermal events that accompanyprogressive heating of the sample are visible.

The glass transition (Tg) is identifiable with a decreasing step, attimes followed by an increase in the baseline caused by relaxationenthalpy. During evaluation of the thermograms the onset temperature ofthe phenomenon (Tg onset) is calculated, regardless of the sample size.The glass transition temperature is a stability index of the powder asit is a prelude to crystallization, which takes place above 100° C. Theexothermic crystallization peak can be integrated and the area subtendedby the curve is an index of the amorphous fraction of the sample.

Preparation of the Mixtures.

The formulations used for the aerosol characterization tests with MSLIwere produced by mixing powders containing the active agents and bulkingagent with the mixture of lactoses. The powders were mixed using anUltra Turrax T10 mixer for a mixing time of 5 minutes consideredsufficient for the 3.5 g of powder of the batches produced. Uniformityof the content was controlled with titer analysis on 10 samples takenfrom different points of the bulk.

The powders were divided in sealed vials and stored inside a doublealuminum foil bag heat sealed with partial vacuum (30%).

The operations of mixing and dividing in vials were carried out inside aglove box in controlled humidity and temperature conditions; maxtemperature 20° C. and environmental relative humidity <35%.

Characterization of the Powder: Respirability Test with MSLI.

The Multi Stage Liquid Impinger (MSLI) is a device that simulates invitro pulmonary deposition of an inhalation formulation. A inhalationformulation, delivered by appropriate inhaler and conveyed into thedevice by aspiration, is deposited in the various stages connected inseries of the impactor as a function of its aerodynamic features, suchas particle size, density, shape. Each stage of the MSLI corresponds toan interval of aerodynamic particle sizes of the powder depositedtherein and the aerodynamic size distribution of the powder is obtainedusing HPLC testing to determine the amount of active agent in eachstage, making it possible to calculate the median aerodynamic diameterand the respirable fraction, considered according to the EuropeanPharmacopoeia with aerodynamic diameter <5.0 μm.

For the respirability test, the powders of the formulations of theexamples were divided into Size 3 HPMC capsules and loaded from RS01powder inhaler—model 7 single-dose, code 239700001AB (Plastiape S.p.A.).

The device was assembled following the instructions for use and theindications of the European Pharmacopoeia.

For test purposes, it is necessary to deliver 10 powder capsules foreach respirability test. The tests can be conducted at differentpressure drops. In the case of the inhaler RS01, the pressure drop of 2KPa corresponds to a flow of 60±2 l/min for 4 seconds and the pressuredrop of 4 KPa records a flow of 96±2 l/min for 2.4 s. derived from apressure drop of 2 Kpa in the system.

The following aerodynamic diameter cut-offs correspond to this flowvalue for each stage.

Aerodynamic range diam. Aerodynamic range diam. Stage 2 KPa (60 ± 2l/min) 4 KPa (96 ± 2 l/min) 1 >13 μm >10.3 μm 2 13.0-6.8 μm 10.3-5.4 μm3 6.8-3.1 μm 5.4-2.5 μm 4 3.1-1.7 μm 2.5-1.3 μm 5 <1.7 μm <1.3 μm(filter):

The respirable fraction (Fine Particle Fraction) comprises particleshaving a median aerodynamic diameter of less than 5 μm and is calculatedusing specific software (CITDAS Copley).

The aerodynamic parameters of an inhalation formulation subjected toMSLI analysis are expressed in terms of:

-   -   Delivered Fraction (DF): i.e. the percentage of the dose of        active agent delivered from the mouthpiece of the inhaler    -   Fine Particle Fraction (FPF): respirable fraction (aerodynamic        diameter <5.0 μm) of active agent expressed as percentage of the        amount delivered.

Quantitative determination of the active agent in each stage wasperformed by HPLC using the test method for titer and related.

Example 1

Example 1 was conducted producing formulations containing FormoterolFumarate or Tiotropium Bromide, which are two active agents sensitive tothe presence of free water in the formulation.

In the case of formoterol, formulations containing different amounts ofleucine and lactose or mannitol were produced.

The example highlights the protective effect of lactose againstformoterol, this protective effect is explained considering that lactoseis capable of producing a scavenger effect against the free waterpresent in the formulation.

To demonstrate this, formulations of 3 types were produced:

-   -   A powder containing exclusively formoterol and leucine    -   2 powders with different lactose contents together with        formoterol and leucine    -   2 powders containing formoterol and leucine in which lactose was        substituted by a different sugar: mannitol

The formulations with lactose tend to acquire moisture over time, withconsequent decrease of Tg, but degradation over time is limited. Thislimited degradation is presumably due to a scavenger effect produced bythe lactose against the water, which is thus trapped in a rigidstructure and prevented from reacting with the other components.Differently, the formulation without lactose which was alreadycrystalline undergoes chemical degradation.

Of the two formulations containing lactose, the one with 50% is better,as it is more stable over time.

Formulations containing tiotropium, leucine and lactose at differentconcentrations of tiotropium were also produced to assess the minimumconcentration of active agent in the formulation so as to obtain astable powder.

TABLE 1A Tween Formoterol Tiotropium Leucine Lactose Mannitol 80 Watercontent (%) Ex. (%) (%) (%) (%) (%) (%) T0 T28 days 1 5.00 95.00 0.9 0.92 5.00 70.00 25.00 1.4 1.8 3 5.00 45.00 50.00 2.1 2.7 4 5.00 70.00 25.000.9 0.9 5 5.00 45.00 50.00 1.0 0.9 6 0.06 50.00 49.44 0.50 1.2 2.0 73.00 50.00 46.50 0.50 3.0 2.5 8 6.00 50.00 43.50 0.50 2.4 1.3

TABLE 1B Degradation products Tg (° C.) P. size (VMD) (%) Ex. T0 T28days T0 T28 days T0 T28 days 1 Not detected Not detected 2.6 2.7 0.6 0.92 62.7 56.9 2.0 1.9 0.4 0.4 3 66.3 57.5 1.6 1.6 0.3 0.3 4 Not detectedNot detected 2.3 2.2 0.2 1.6 5 Not detected Not detected 1.6 1.6 0.1 1.46 72.7 62.2 2.7 2.8 0.7 1.5 7 58.5 60.5 1.7 1.7 0.1 0.5 8 Not detectedNot detected 1.7 1.7 0.3 0.5

Example 2

The example was conducted producing formulations containing as activeagent Budesonide, defined as HLSA Bud, formulated with lactose andleucine (Table 3), formulations containing as active agent FormoterolFumarate, defined as HLSA FF, formulated with lactose and leucine (Table2).

The lactose powders used were Respitose® SV003 (DFE Pharma, Goch, D) eLacto-Sphere® MM3 (Microsphere SA, Ponte Cremenaga, Lugano CH).

Identification of the optimal coarse/fine lactose ratio was based on theproduction of formulations with increasing amounts of LactoSphere MM3 informulations containing HLSA FF, HLSA Bud and Respitose SV003 due to theaerodynamic characterization of each single formulation. The parametersevaluated through the MSLI test were the Fine Particle Fraction (FPF %)and the Delivered Fraction (DF %) in conditions with pressure drop of 4KPa using the inhaler RS01 (Plastiape, Osnago, Lecco, I).

The results obtained show that a ratio of 91:9 Respitose SV003 (coarselactose) and MM3 (fine lactose) guarantees high values of Delivered Dose(%) and high Fine Particle Fraction (%) respirability, at the same timeensuring that the mixture remains homogeneous over time.

TABLE 2 Powder containing Formoterol Fumarate (HLSA FF 2.25%) FormoterolFumarate 2.25% Leucine 20.0% Lactose 77.25%  Tween 80  0.5%

TABLE 3 Powder containing Budesonide (HLSA Bud 8%) Budesonide 8.0%Leucine 50.0% Lactose 41.5% Tween 80 0.5%

TABLE 4 Powder containing Lactose Ex. Respitose SV003 Lactosphere MM3 9100.0% 0.0% 10 98.0% 2.0% 11 94.0% 6.0% 12 91.0% 9.0% 13 90.0% 10.0% 1485.0% 15.0% 15 80.0% 20.0% 16 70.0% 30.0%

TABLE 5 Lactose mix from Ex. HLSA FF HLSABDS Table 4 17 0.5% 2.5% Fromexample 9 97% 18 0.5% 2.5% From example 10 97% 19 0.5% 2.5% From example11 97% 20 0.5% 2.5% From example 12 97% 21 0.5% 2.5% From example 13 97%22 0.5% 2.5% From example 14 97% 23 0.5% 2.5% From example 15 97% 240.5% 2.5% From example 16 97%

TABLE 6 DF % DF % FPF % FPF % Ex. Formoterol Budesonide FormoterolBudesonide 17 81.4% 85.3% 59.8% 51.5% 18 81.3% 87.0% 59.7% 49.1% 1986.3% 91.3% 69.2% 68.7% 20 88.3% 90.6% 67.6% 69.6% 21 89.2% 92.8% 65.6%63.8% 22 95.5% 97.4% 63.0% 66.5% 23 80.8% 79.6% 53.9% 66.8% 24 80.6%80.5% 48.2% 63.1%

Example 3

Example 3 was conducted producing formulations containing as activeagent Budesonide (defined as HLSA Bud in the table), formulated withlactose and leucine, formulations containing as active agent FormoterolFumarate (defined as HLSA FF in the table), formulated with lactose andleucine and formulations containing as active agent Tiotropium (definedas HLSA Tio in the table) formulated with lactose and leucine. Theseformulations were mixed with a lactose powder containing a mixture ofRepitose SV003 and of LactoSphere MM3.

Some formulations containing Formoterol and tiotropium at lowpercentages were also mixed with a powder containing lactose andleucine, in which lactose is used as filler to form a Bulking Agent(defined as BA in the table) or powder containing leucine and lactosebut without active agent.

The powders contained in the composition according to the invention areas follows:

TABLE 7 Powder containing Formoterol Fumarate (HLSA FF 2.25%) FormoterolFumarate 2.25% Leucine 20.0% Lactose 77.25%  Tween 80  0.5%

TABLE 8 Powder containing Formoterol Fumarate (HLSA FF 4.5%) FormoterolFumarate 4.5% Leucine 20.0% Lactose 75.0% Tween 80 0.5%

TABLE 9 Powder containing Budesonide (HLSA Bud 8%) Budesonide 8.0%Leucine 50.0% Lactose 41.5% Tween 80 0.5%

TABLE 10 Powder containing Tiotropium (HLSA Tio 1.5%) Tiotropium 1.5%Leucine 50.0% Lactose 48.0% Tween 80 0.5%

TABLE 11 Powder containing Tiotropium (HLSA Tio 3%) Tiotropium 3.0%Leucine 50.0% Lactose 46.5% Tween 80 0.5%

TABLE 12 Powder containing Tiotropium (HLSA Tio 6%) Tiotropium 6.0%Leucine 50.0% Lactose 43.5% Tween 80 0.5%

TABLE 13 Lactose mix Respitose ® SV003 91% LactoSphere ® MM3  9%

TABLE 14 Bulking Agent (BA) Leucine  50% Lactose 49.5% Tween 80  0.5%

The powders were mixed according to the methods described above, inorder to obtain formulations containing Budesonide and Formoterol,Tiotropium and mixtures thereof, in a dose of powder of 15 mg.

The parameters evaluated through the MSLI test were the Fine ParticleFraction (FPF %) and the Delivered Fraction (DF %) in conditions withpressure drop of 2 KPa using the inhaler RS01 (Plastiape, Osnago, Lecco,

TABLE 15 HLSA HLSA HLSA HLSA HLSA HLSA FF FF Tio Tio Tio Bud Lactose DFFPF Ex 2.25% 4.5% 1.5% 3% 6% 8% BA Mix % % 17 0.80% — — — — — — 99.20%87.1% 40.8% 18 0.80% — — — — — 10.00% 89.20% 93.3% 60.4% 19 0.80% — — —— 8.00% 91.20% 88.4% 70.8% Formoterol Formoterol 89.9% 73.1% BudesonideBudesonide 20 — 0.40% — — — — — 99.60% 86.4% 50.5% 21 — 0.40% — — — —10.00% 89.60% 85.0% 82.5% 22 — — — — — 8.00% — 92.00% 89.0% 74.4% 23 — —2.67% — — — — 97.33% 88.3% 77.2% 24 — — — 1.33% — — — 98.67% 85.6% 70.7%25 — — — 1.33% — — 10.00% 88.67% 93.9% 79.6% 26 — — — 1.33% — 8.00% —90.67% 89.2% 73.3% Tiotropium Tiotropium 93.0% 74.0% BudesonideBudesonide 27 — — — — 0.67% — — 99.33% 82.4% 48.2% 28 — — — — 0.67% —10.00% 89.33% 92.8% 69.4% 29 — — — — 0.67% 8.00% — 91.33% 89.2% 73.3%Tiotropium Tiotropium 93.0% 74.0% Budesonide Budesonide 30 0.80% — —1.33% — 8.00% — 89.87% 89.9% 76.2% Tiotropium Tiotropium 95.0% 76.3%Budesonide Budesonide 89.8% 74.0% Formoterol Formoterol

Example 4

The example was conducted analyzing some products currently on themarket containing Formoterol, Budesonide, Tiotropium or combinationsthereof (Table 16). Crystalline mixtures of budesonide and formoterol(i.e. not formulated according to the present invention by spray drying)with lactose mixtures with different particle sizes according to thepresent invention (Table 17A and 17B) were also analyzed.

The products available on the market used for comparison were:

-   -   Symbicort® produced by Astrazeneca with Budesonide/Formoterol        Fumarate ratio expressed in μg of 160/4.5.    -   Miflonide®—Budesonide 400 mcg, Novartis Farma S.p.A. —21040        Origgio (VA), Italy    -   Foradil®—Formoterol Fumarate 12 mcg, Novartis Farma S.p.A.—21040        Origgio (VA), Italy    -   Spiriva®—Tiotropium Bromide, 18 mcg, Boehringer Ingelheim,        Italia S.p.A., (MI), Italy

The aerodynamic performance of the commercial products was assessed withthe MSLI test conducted with a pressure drop of 4 KPa.

The example was conducted in order to assess the aerosol performance ofthe composition according to the present invention, emphasizing how thiscomposition (see Example 3) can be administered maintaining a high doseof drug delivered through the mouthpiece and a percentage of fineparticles able to ensure that the amount of drug deposited in the siteof action is capable of performing the correct pharmacological action.

The aerodynamic performance of a dose of 15 mg of each formulationcontaining crystalline active agents was assessed with the MSLI testconducted at the pressure drop of 2 KPa and 60 l/min.

TABLE 16 FPF % FPF % FPF % Formoterol Budesonide Tiotropium Symbicort ®35.6% 38.4% — 160/4.5 Foradil ® 33.8% — — Miflonide ® — 26.1% —Spiriva ® — — 54.8%

TABLE 17A Powder of crystalline Budesonide, Formoterol and Tiotropium C1C2 C3 C4 Budesonide  0.64%  0.64% — — Micronized Ph. Eur., IndustrialeChimica, S.r.l, Saronno, VA, Italy Formoterol  0.018% —  0.018% —Fumarate Dihydrate, Ph Eur. 7th Ed., Lusochimica, S.p.A., Lomagna, LC,Italy Tiotropium — — —  0.04% Bromide, Euroasian Chemicals PVT LTD,Mumbai - 400001 India Lactose Mix 99.342% 99.36% 99.982% 99.94%(according to Table XX)

TABLE 17B FPF % FPF % FPF % Formoterol Budesonide Tiotropium C1 2.1%42.8% — C2 — 45.8% — C3 3.7% — — C4 — — 1.7%

1. A pharmaceutical composition for inhalatory use in powder form, whichcomprises: a) a first powder comprising at least a powder (a₁)comprising an active agent or a pharmaceutically acceptable saltthereof, in an amount greater than 1% by weight of said powder, leucinein amount from 5 to 70% by weight of said powder, a sugar in amount from20 to 90% by weight of said powder; b) a second powder comprising amixture of a first lactose which has an X50 from 35 to 75 μm, with asecond lactose which has an X50 from 1.5 to 10 μm, the content of saidfirst lactose and second lactose in said mixture being respectively from85% to 96% and from 4% to 15%, wherein the ratio by weight of said firstpowder and said second powder is from 1/5 to 1/100, and said compositionhas a fine particle fraction (FPF) greater than 60% and a deliveredfraction (DF) greater than 80%.
 2. The composition according to claim 1,wherein said first powder comprises a third powder (a₂) comprisingleucine in an amount from 5 to 70% by weight of said third powder andlactose in an amount from 20 to 90% by weight of said third powder. 3.The composition according to claim 1, wherein said first powdercomprises a fourth powder (a₃) comprising an active agent or apharmaceutically acceptable salt thereof, in an amount greater than 1%by weight of said fourth powder, leucine in an amount from 5 to 70% byweight of said fourth powder, and a sugar in an amount from 20 to 90% byweight of said fourth powder.
 4. The composition according to claim 1,wherein said active agent is a hydrolyzable active agent.
 5. Thecomposition according to claim 1, wherein said active agent is selectedfrom the group consisting of: short and long acting bronchodilatorinhalers, corticosteroids, anti-cholinergics, antibiotics, mucolytics,heparin and its derivatives, substances with antioxidant action.
 6. Thecomposition according to claim 1, wherein said sugar is selected fromthe group consisting of: lactose, trehalose, sucrose and maltodextrin.7. The composition according to claim 1, wherein said leucine is in anamount from 18 to 55% by weight.
 8. The composition according to claim1, wherein said sugar is in an amount from 40 to 80% by weight.
 9. Thecomposition according to claim 1, wherein said powders comprisingleucine comprise a surfactant in an amount from 0.2 to 2% by weight ofthe powder.
 10. The composition according to claim 7, wherein saidsurfactant is selected from the group consisting of benzalkoniumchloride, cetrimide, docusate sodium, glyceryl monooleate, sorbitanesters, sodium lauryl sulfate, polysorbates, phospholipids, bile salts,block copolymers of polyoxyethylene and polyoxypropylene.
 11. Thecomposition according to claim 7, wherein said surfactant is in anamount from 0.4 to 0.8% by weight.
 12. The composition according toclaim 1, wherein said first powder has an X50 less than 5 μm.
 13. Thecomposition according to claim 1, wherein the content of said firstlactose and second lactose in said mixture comprised in said secondpowder being respectively comprised from 91 to 95% and from 5 to 9%. 14.A kit for the administration of a drug as inhalation powder, comprisinga metered amount of the composition according to claim 1 and a devicefor inhalation.
 15. The composition according to claim 2, wherein saidfirst powder comprises a fourth powder (a₃) comprising an active agentor a pharmaceutically acceptable salt thereof, in an amount greater than1% by weight of said fourth powder, leucine in an amount from 5 to 70%by weight of said fourth powder, and a sugar in an amount from 20 to 90%by weight of said fourth powder.
 16. The composition according to claim2, wherein said active agent is a hydrolyzable active agent.
 17. Thecomposition according to claim 3, wherein said active agent is ahydrolyzable active agent.
 18. The composition according to claim 2,wherein said active agent is selected from the group consisting of:short and long acting bronchodilator inhalers, corticosteroids,anti-cholinergics, antibiotics, mucolytics, heparin and its derivatives,substances with antioxidant action.
 19. The composition according toclaim 3, wherein said active agent is selected from the group consistingof: short and long acting bronchodilator inhalers, corticosteroids,anti-cholinergics, antibiotics, mucolytics, heparin and its derivatives,substances with antioxidant action.
 20. The composition according toclaim 4, wherein said active agent is selected from the group consistingof: short and long acting bronchodilator inhalers, corticosteroids,anti-cholinergics, antibiotics, mucolytics, heparin and its derivatives,substances with antioxidant action.